DNA has a molecular ambulance

_{Denyse O'Leary

September 1, 2015

Cell biology, Genetics, News}

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A molecular motor that transports damaged DNA is also necessary for its repair.

Double-strand breaks in DNA are a source of stress and sometimes death for cells. But the breaks can be fixed if they find their way to repair sites within the cell. In yeast, one of the main repair sites resides on the nuclear envelope where a set of proteins, including nuclear pore subcomplex Nup84, serves as a molecular hospital of sorts. The kinesin-14 motor protein complex, a “DNA ambulance,” moves the breaks to repair sites, according to a new study in Nature Communications (1).

“To think of motor proteins moving DNA inside cells-it was very surprising,” said corresponding author Karim Mekhail at the University of Toronto. “In the beginning, we thought that there must be some other way to explain these findings. But the more we tested, the more we realized that kinesin-14 must be mediating the movement of damaged DNA.” More.

Just a random event, for sure. Like that plague of Boltzmann brains floating over your desks… Oh wait, you better not think this one out too clearly.

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Comments

Heck, I shoulda thought of that. The multiverse starts here!Axel_{September 7, 2015
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From a cage-fighting perspective Alicia has been body slammed and knocked out. "Toodaloo" was all she had- and she ran away after another huge misrepresentation. "you moron" was very accurate and I doubt Alicia Cartelli is a lady, Axel.Virgil Cain_{September 6, 2015
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From a cage-fighting perspective it looks that way, though, Virg. It may be precise, but I think 'twaddle' is a passable precis of 'misrepresentation and equivocation'. But 'you moron' is not very gallant, said to a lady, Virg, however loudly it made me explode with laughter! 'Toodaloo' was good, Alicia!Axel_{September 6, 2015
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LoL! @ Axel- Alicia is winning by misrepresentation and equivocation. Oh wait, that's not winning at all...Virgil Cain_{September 6, 2015
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Dionisio:
I don’t recall seeing anywhere in the available literature that I reviewed any reference to direct bonds between the codons and the AAs. However, I know nothing about biology, hence it’s possible that your interlocutor has access to paywalled academic papers that contain the latest research information unavailable to you and me.
That would be big news and trumpeted by evos everywhere. No trumpets means no big news. :cool:Virgil Cain_{September 6, 2015
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I love these invective 'rumbles'! Two cage-fighters I think Alicia is winning as she manages to send Virg into transports of fury. But that may be because she's doing the atheists' thang of talking genuine twaddle and putting her 'case' across with a certain feline hauteur, that's getting under Virg's skin. Even her name is kinda feline, isn't it? Alicia. Slides rather than rolls off the tongue. But I hope she's not like the French general, Giraud, who was described by a fellow-officer as having 'the uncomprehending eyes of a porcelain cat - so stately.. and stupid.' I dinnae ken though. So, I may be reviled by both, though I think they have enough scientific 'stuff' to keep them occupied.Axel_{September 6, 2015
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It's the following she finds funny:
If the DNA has the codons then the mRNA would have the anti-codons and the tRNA would have the original codons, in RNA format.
She doesn't realize that is all perspective. That is why I included the "If" at the front of both sentences. Meaning Alicia is also ignorant of EnglishVirgil Cain_{September 6, 2015
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Virgil Cain:
If you say the mRNA has the codons then the tRNA would have the anti-codons.
I just don't see what Alicia finds so hilariously funny about this.Mung_{September 6, 2015
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Virgil Cain @103
There aren’t any bonds between the mRNA codon and the amino acid they represent.
That seems correct. Apparently, for every canonical AA associated with the genomic code there's a specific aaRS enzyme that recognizes the tRNA anticodon domain and attaches the corresponding AA to the tRNA CCA tail. I don't recall seeing anywhere in the available literature that I reviewed any reference to direct bonds between the codons and the AAs. However, I know nothing about biology, hence it's possible that your interlocutor has access to paywalled academic papers that contain the latest research information unavailable to you and me. BTW, you may talk all you want to about biology or anything else you want to. Don't let the voices of this dying world tell you what to do. They have no clue whatsoever, but sadly they are not aware of the miserable condition they're in. I was in that same condition for a long time, but God graciously pulled me out of that path that leads to eternal separation from His glory. Hallelujah! I pray for our interlocutors. They don't know that God loves them too. We are not better than them. Perhaps some of them will be graciously rescued from their hopeless situation before it's too late.Dionisio_{September 6, 2015
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Alicia- CONTEXT- we were talking about the mRNA codons- so grow up.
And no, codons cannot be on both the sense/antisense strands of DNA, you would get two different predicted protein sequences from them.
Codons can be on both, Alicia. Both sides can be transcribed. That means it all depends on which is the codon. But tat wasn't even the point you moron. Your ignorance, while amusing, means nothing.Virgil Cain_{September 6, 2015
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Virg, your statement was: "There isn’t any chemical bonds between nucleotides and amino acids in the observed translation systems." And it is completely and utterly incorrect. And no, codons cannot be on both the sense/antisense strands of DNA, you would get two different predicted protein sequences from them. Wrong again Virg, thanks for playing. Goodbye!Alicia Cartelli_{September 6, 2015
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Alicia- You screwed up because you don't know anything. There aren't any bonds between the mRNA codon and the amino acid they represent. I told you that and you still choose willful ignorance. Biologists also say the codon is on the DNA- sense/ anti-sense. So stuff it. You are obviously just an ignorant arse. My comment in 76 could be understood by a middle school biology student. It's very telling that it went over your pointed head.Virgil Cain_{September 6, 2015
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Virg, buddy, remember when you tried to tell me there were no covalent bonds between RNA and amino acids in the translational system and I had to correct you? The first half of your comment 76 also makes no sense. The codon is always on the mRNA and anticodon always on the tRNA. End of story. Dio actually sounds like he knows what he's talking about more than you do. (That's not good for you). I really need you to stop trying to talk about biology, I might die from laughter.Alicia Cartelli_{September 6, 2015
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Alicia Cartelli- Please go soak your head as you are lightyears behind and you don't have a clue. You are always good for a laugh, though. Come back when your position has an explanation for what we observe happening inside a cell.Virgil Cain_{September 6, 2015
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No, mapou, we’re not even close to even. You guys are lightyears behind and not going anywhere fast. Like I said, Upright, always a good chat with you.Alicia Cartelli_{September 6, 2015
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Perry Marshall has a challenge for evos on the origin of information: The Origin of Information: How to Solve It Here is the setup: The Atheist’s Riddle: Skeptics Attempt To Solve ItVirgil Cain_{September 6, 2015
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UB Thanks for the email answer. Have a good weekend.Dionisio_{September 5, 2015
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Virgil Cain @92
Programming- specifically the enzymes are programmed to recognize their specific tRNAs.
Yes, the fact that a precise spatiotemporal regulatory system guarantees the presence of tRNA carriers and specific aaRS enzymatic proteins for catalyzing the association of the translated mRNA codons with their corresponding AAs, in order to synthesize other proteins, is indeed amazing. Complex complexity. :)Dionisio_{September 5, 2015
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FLIGHT: The Genius of Birds – Embryonic development – video http://www.youtube.com/watch?v=-Ah-gT0hTto
Moreover, in humans themselves, as all teenagers are well aware, reproductive capability does not 'come online' until practically all of the goal directed process of development has already occurred. To say that Darwinists lack a coherent explanation as to how these amazing, massively, goal directed processes of development can possibly occur, with reproductive capability being so far downstream in the process, is a gross understatement. When one considers the sheer magnitude of the developmental process involved in creating a human out of a billion-trillion protein molecules, "without foresight" is certainly not the term that comes to one's mind,
Alexander Tsiaras: Conception to birth — visualized http://www.youtube.com/watch?v=fKyljukBE70 Mathematician Alexander Tsiaras on Human Development: "It's a Mystery, It's Magic, It's Divinity" - March 2012 Excerpt: 'The magic of the mechanisms inside each genetic structure saying exactly where that nerve cell should go, the complexity of these, the mathematical models on how these things are indeed done, are beyond human comprehension. Even though I am a mathematician, I look at this with the marvel of how do these instruction sets not make these mistakes as they build what is us. It's a mystery, it's magic, it's divinity.' http://www.evolutionnews.org/2012/03/mathematician_a057741.html Frank Turek Christ Community Church (April 2015) - video - (goal directed embryogenesis 27:10 minute mark) https://youtu.be/iKFfq-IwcrM?t=1629 HOW BIOLOGISTS LOST SIGHT OF THE MEANING OF LIFE — AND ARE NOW STARING IT IN THE FACE - Stephen L. Talbott - May 2012 Excerpt: “If you think air traffic controllers have a tough job guiding planes into major airports or across a crowded continental airspace, consider the challenge facing a human cell trying to position its proteins”. A given cell, he notes, may make more than 10,000 different proteins, and typically contains more than a billion protein molecules at any one time. “Somehow a cell must get all its proteins to their correct destinations — and equally important, keep these molecules out of the wrong places”. And further: “It’s almost as if every mRNA [an intermediate between a gene and a corresponding protein] coming out of the nucleus knows where it’s going” (Travis 2011),,, Further, the billion protein molecules in a cell are virtually all capable of interacting with each other to one degree or another; they are subject to getting misfolded or “all balled up with one another”; they are critically modified through the attachment or detachment of molecular subunits, often in rapid order and with immediate implications for changing function; they can wind up inside large-capacity “transport vehicles” headed in any number of directions; they can be sidetracked by diverse processes of degradation and recycling... and so on without end. Yet the coherence of the whole is maintained. The question is indeed, then, “How does the organism meaningfully dispose of all its molecules, getting them to the right places and into the right interactions?” The same sort of question can be asked of cells, for example in the growing embryo, where literal streams of cells are flowing to their appointed places, differentiating themselves into different types as they go, and adjusting themselves to all sorts of unpredictable perturbations — even to the degree of responding appropriately when a lab technician excises a clump of them from one location in a young embryo and puts them in another, where they may proceed to adapt themselves in an entirely different and proper way to the new environment. It is hard to quibble with the immediate impression that form (which is more idea-like than thing-like) is primary, and the material particulars subsidiary. Two systems biologists, one from the Max Delbrück Center for Molecular Medicine in Germany and one from Harvard Medical School, frame one part of the problem this way: "The human body is formed by trillions of individual cells. These cells work together with remarkable precision, first forming an adult organism out of a single fertilized egg, and then keeping the organism alive and functional for decades. To achieve this precision, one would assume that each individual cell reacts in a reliable, reproducible way to a given input, faithfully executing the required task. However, a growing number of studies investigating cellular processes on the level of single cells revealed large heterogeneity even among genetically identical cells of the same cell type. (Loewer and Lahav 2011)",,, And then we hear that all this meaningful activity is, somehow, meaningless or a product of meaninglessness. This, I believe, is the real issue troubling the majority of the American populace when they are asked about their belief in evolution. They see one thing and then are told, more or less directly, that they are really seeing its denial. Yet no one has ever explained to them how you get meaning from meaninglessness — a difficult enough task once you realize that we cannot articulate any knowledge of the world at all except in the language of meaning.,,, http://www.netfuture.org/2012/May1012_184.html#2
Moreover as if all that was not completely devastating to the proposed unguided material processes of neo-Darwinian evolution, in metamorphic creatures, such as in butterflies, the miracle of development happens twice before reproductive capability comes online. Dr. Paul Nelson, at the 12:21 minute mark of the following video, comments that metamorphosis is, by all rights, a miracle with no possible naturalistic explanation as to how it came about:
The Miracle of Development Part 1 – Origins with Dr. Paul A. Nelson – video – April 2013 http://www.youtube.com/watch?v=JD9qMvz6T90&feature=player_detailpage#t=736s
Moreover this miracle of metamorphosis is widespread:
From Discovering Intelligent Design: My How You've Changed - May 26, 2013 Excerpt: Holometabolism (complete metamorphosis) is the most common and complicated form of insect maturation. The diverse group that undergoes this type of process includes butterflies, moths, beetles, fleas, bees, ants, and many kinds of flies.,,, It is exceedingly difficult to understand the origin of holometabolism in Darwinian evolutionary terms. Neither the larval nor the pupal stage is capable of reproduction -- only the adult is. In particular, the pupal stage is an all-or nothing proposition. It must complete the process and become an adult, or it will die without ever reproducing. The liquefied organism must be completely rebuilt. For this to occur, large amounts of information -- encoding the larval body plan, the mechanisms of transformation during metamorphosis, and the adult body plan -- must exist before the larva enters this stage. An organism could not survive complete metamorphosis unless the entire process was fully programmed from the beginning. Such a large jump in complexity requires forethought and planning -- things that don't exist in Darwinian evolution. As one evolutionary entomologist acknowledges: "... the biggest head-scratcher in evolutionary biology would have to be the origin of the holometabolous insect larva." http://www.evolutionnews.org/2013/05/from_discoverin_3072521.html
Moreover, besides butterflies, and other insects, it turns out that some, (perhaps many?), of the Cambrian creatures also harbored this amazing '2 for 1' metamorphic capability that butterflies and other insects possess:
The Enigma of Metamorphosis Is Hardly Limited to Butterflies - October 2011 Excerpt: Even more mysteriously, it appears that the most ancient phyla were metamorphic from the beginning, based on the few larval forms that have been preserved. This suggests that these Cambrian animals had not one but two or more developmental stages at the outset,,,, http://www.evolutionnews.org/2011/10/the_enigma_of_metamorphosis_is051541.html Metamorphosis Is Widespread - Ann Gauger - video http://www.youtube.com/watch?v=GkD-jd1imaI
bornagain77_{September 5, 2015
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as to:
Alicia Cartelli: Nature is the ultimate trial-and-error experiment, it hasn’t needed foresight to produce the diversity of species (…) we see today.
Aside from the fact that atheists live in outright denial of the design and purpose, (i.e. foresight), they see in nature and in life:
"Yet the living results of natural selection overwhelmingly impress us with the appearance of design as if by a master watchmaker, impress us with the illusion of design and planning." Richard Dawkins - "The Blind Watchmaker" - 1986 - page 21 Michael Behe - Life Reeks Of Design - 2010 – video https://www.youtube.com/watch?v=Hdh-YcNYThY living organisms "appear to have been carefully and artfully designed" Lewontin "The appearance of purposefulness is pervasive in nature." George Gaylord Simpson
Francis Crick, co-discoverer of DNA, seems to have been particularly haunted by this illusion of seeing design everywhere he looked in molecular biology:
"Biologists must constantly keep in mind that what they see was not designed, but rather evolved." Francis Crick - What Mad Pursuit "Organisms appear as if they had been designed to perform in an astonishingly efficient way, and the human mind therefore finds it hard to accept that there need be no Designer to achieve this" Francis Crick - What Mad Pursuit - p. 30
And aside from the fact that it is impossible for atheists to put their money where their mouth is and to live their lives as if there truly were no purpose for their life:
The Heretic - Who is Thomas Nagel and why are so many of his fellow academics condemning him? - March 25, 2013 Excerpt:,,,Fortunately, materialism is never translated into life as it’s lived. As colleagues and friends, husbands and mothers, wives and fathers, sons and daughters, materialists never put their money where their mouth is. Nobody thinks his daughter is just molecules in motion and nothing but; nobody thinks the Holocaust was evil, but only in a relative, provisional sense. A materialist who lived his life according to his professed convictions—understanding himself to have no moral agency at all, seeing his friends and enemies and family as genetically determined robots—wouldn’t just be a materialist: He’d be a psychopath. http://www.weeklystandard.com/articles/heretic_707692.html?page=3 Darwin's Robots: When Evolutionary Materialists Admit that Their Own Worldview Fails - Nancy Pearcey - April 23, 2015 Excerpt: Even materialists often admit that, in practice, it is impossible for humans to live any other way. One philosopher jokes that if people deny free will, then when ordering at a restaurant they should say, "Just bring me whatever the laws of nature have determined I will get.",,, When I teach these concepts in the classroom, an example my students find especially poignant is Flesh and Machines by Rodney Brooks, professor emeritus at MIT. Brooks writes that a human being is nothing but a machine -- a "big bag of skin full of biomolecules" interacting by the laws of physics and chemistry. In ordinary life, of course, it is difficult to actually see people that way. But, he says, "When I look at my children, I can, when I force myself, ... see that they are machines." Is that how he treats them, though? Of course not: "That is not how I treat them.... I interact with them on an entirely different level. They have my unconditional love, the furthest one might be able to get from rational analysis." Certainly if what counts as "rational" is a materialist worldview in which humans are machines, then loving your children is irrational. It has no basis within Brooks's worldview. It sticks out of his box. How does he reconcile such a heart-wrenching cognitive dissonance? He doesn't. Brooks ends by saying, "I maintain two sets of inconsistent beliefs." He has given up on any attempt to reconcile his theory with his experience. He has abandoned all hope for a unified, logically consistent worldview. http://www.evolutionnews.org/2015/04/when_evolutiona095451.html Existential Argument against Atheism - November 1, 2013 by Jason Petersen 1. If a worldview is true then you should be able to live consistently with that worldview. 2. Atheists are unable to live consistently with their worldview. 3. If you can’t live consistently with an atheist worldview then the worldview does not reflect reality. 4. If a worldview does not reflect reality then that worldview is a delusion. 5. If atheism is a delusion then atheism cannot be true. Conclusion: Atheism is false. http://answersforhope.com/existential-argument-atheism/
And aside from the fact that it is impossible for atheists to even do science in the first place without presupposing teleology on some level:
tel·e·ol·o·gy Philosophy the explanation of phenomena by the purpose they serve rather than by postulated causes. Theology the doctrine of design and purpose in the material world. Design Thinking Is Hardwired in the Human Brain. How Come? - October 17, 2012 Excerpt: "Even Professional Scientists Are Compelled to See Purpose in Nature, Psychologists Find." The article describes a test by Boston University's psychology department, in which researchers found that "despite years of scientific training, even professional chemists, geologists, and physicists from major universities such as Harvard, MIT, and Yale cannot escape a deep-seated belief that natural phenomena exist for a purpose" ,,, Most interesting, though, are the questions begged by this research. One is whether it is even possible to purge teleology from explanation. http://www.evolutionnews.org/2012/10/design_thinking065381.html "virtually all of science proceeds as if ID is true – it seeks elegant and efficient models; it reverse engineers biological systems; it describes evolution in teleological terms; it refers to natural forces and laws as if there is some kind of prescriptive agency guiding matter and energy; it assumes that the nature of the universe and human comprehensive capacity have some sort of truthful, factual correspondence." William J Murray "to say that a stone falls to earth because it's obeying a law, makes it a man and even a citizen" - CS Lewis
And aside from the fact that it is impossible for atheists, or anybody else for that matter, to describe molecular biology without abundant reference to words that imply agency, purpose, and design, (i.e. foresight):
The 'Mental Cell': Let’s Loosen Up Biological Thinking! - Stephen L. Talbott - September 9, 2014 Excerpt: Many biologists are content to dismiss the problem with hand-waving: “When we wield the language of agency, we are speaking metaphorically, and we could just as well, if less conveniently, abandon the metaphors”. Yet no scientist or philosopher has shown how this shift of language could be effected. And the fact of the matter is just obvious: the biologist who is not investigating how the organism achieves something in a well-directed way is not yet doing biology, as opposed to physics or chemistry. Is this in turn just hand-waving? Let the reader inclined to think so take up a challenge: pose a single topic for biological research, doing so in language that avoids all implication of agency, cognition, and purposiveness1. One reason this cannot be done is clear enough: molecular biology — the discipline that was finally going to reduce life unreservedly to mindless mechanism — is now posing its own severe challenges. In this era of Big Data, the message from every side concerns previously unimagined complexity, incessant cross-talk and intertwining pathways, wildly unexpected genomic performances, dynamic conformational changes involving proteins and their cooperative or antagonistic binding partners, pervasive multifunctionality, intricately directed behavior somehow arising from the interaction of countless players in interpenetrating networks, and opposite effects by the same molecules in slightly different contexts. The picture at the molecular level begins to look as lively and organic — and thoughtful — as life itself. http://natureinstitute.org/txt/st/org/comm/ar/2014/mental_cell_23.htm Life, Purpose, Mind: Where the Machine Metaphor Fails - Ann Gauger - June 2011 Excerpt: I'm a working biologist, on bacterial regulation (transcription and translation and protein stability) through signalling molecules, ,,, I can confirm the following points as realities: we lack adequate conceptual categories for what we are seeing in the biological world; with many additional genomes sequenced annually, we have much more data than we know what to do with (and making sense of it has become the current challenge); cells are staggeringly chock full of sophisticated technologies, which are exquisitely integrated; life is not dominated by a single technology, but rather a composite of many; and yet life is more than the sum of its parts; in our work, we biologists use words that imply intentionality, functionality, strategy, and design in biology--we simply cannot avoid them. Furthermore, I suggest that to maintain that all of biology is solely a product of selection and genetic decay and time requires a metaphysical conviction that isn't troubled by the evidence. Alternatively, it could be the view of someone who is unfamiliar with the evidence, for one reason or another. But for those who will consider the evidence that is so obvious throughout biology, I suggest it's high time we moved on. - Matthew http://www.evolutionnews.org/2011/06/life_purpose_mind_where_the_ma046991.html#comment-8858161 The formal Darwinism project - June 2015 Excerpt: Today, as molecular biologists choose to call some of their discoveries ‘mechanisms’, and ascribe ‘functions’ to enzymes, they use purposive language and so they also adopt the design approach. It is arguably impossible to undertake work in many areas of biology without doing so: purpose in explanations has great power, and attempts to do without it in ethology,,, have long ago been abandoned as unworkable. of note: *Ethology is the scientific and objective study of animal behaviour https://scientiasalon.wordpress.com/2015/06/15/the-formal-darwinism-project/
Aside from all that hidden teleology that is in the atheists worldview, in regards to goal directed processes, (i.e. teleology), atheist have another huge elephant in the living room that they live in denial of. Specifically, embryological development, where one cell turns into the final 'reproducing adult product' of trillions of cells, is clearly a massively goal directed process.
The Deeper Issues of the Worm Video Debate: P.Z. Myers's Misdirection - Paul Nelson - May 7, 2015 (with C. elegans video link) Excerpt: ,,,while Myers agrees that evolution possesses no foresight, he overlooks the key logical point that natural selection operates only downstream of successful (i.e., functional) novel variations.,,, Given that reproduction is a necessary condition of natural selection, however, selection is powerless to act until reproductive capability comes online. Randomly arising mutations must therefore construct novel developmental pathways "on their own" -- with crash-and-burn of the whole system as the most likely result.,, http://www.evolutionnews.org/2015/05/the_deeper_issu095891.html
bornagain77_{September 5, 2015
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Dionisio- You are doing great. There isn't much more to it- for example getting the right tRNA to the ribosome at the right time.Virgil Cain_{September 5, 2015
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UB, Virgil Cain Here's some additional information to answer my own questions posted @88:
The attachment of amino acids to the 3?-end of tRNAs is catalyzed by the aminoacyl-tRNA synthetase (aaRS) family of proteins. aaRSs are ubiquitous and essential but only eukaryotes and a handful of bacteria have the full set of 20 enzymes, one for each canonical amino acid in the genetic code.
tRNAs: Cellular barcodes for amino acids Edited by Manuel Santos Rajat Banerjee, Shawn Chen, Kiley Dare, Marla Gilreath, Mette Praetorius-Ibba, Medha Raina, Noah M. Reynolds, Theresa Rogers, Hervé Roy, Srujana S. Yadavalli, Michael Ibba DOI: http://dx.doi.org/10.1016/j.febslet.2009.11.013 http://www.febsletters.org/article/S0014-5793(09)00906-5/abstract

It seems like the association between the anticodons and the AAs is facilitated by the existence of a specific enzyme from the aaRS family for each canonical AA in the genetic code, although apparently there are some variations of that 'script' as explained in the above referenced paper. Apparently every tRNA anticodon can be associated with the catalytic effect of a corresponding aaRS enzyme in order to attach the corresponding AA to the CCA tail of the given tRNA molecule. The aaRS enzymes seem to recognize both the anticodon domain and the CCA tail of the tRNA molecules, hence they can mediate the association between each mRNA codon and the corresponding canonical AA in the genetic code. Did I get this right this time? Again, I had not studied the transcription/translation mechanisms, but I'm glad I looked into this now, so I could understand what y'all were discussing about. The transcription/translation mechanisms, along with their corresponding post-transcriptional and post-translational mechanisms, undoubtedly very interesting, seem like basic regulatory (common) "tools" compared to higher level mechanisms underlying morphogenesis (morphogen gradient formation and interpretation) and cell fate specification/determination (intrinsic asymmetric division).Dionisio_{September 5, 2015
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REC:
What is your (non-materialist?) explanation?
Programming- specifically the enzymes are programmed to recognize their specific tRNAs.Virgil Cain_{September 5, 2015
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I agree with those who say everything is designed. Of course, everything is designed except God, the Designer. But that is a matter of faith. Our conversation was much narrower as it was about biology. And I paraphrased the well known quote. The only difference between biology and everything else is perhaps that in biology design is scientifically recognizable (and yet that the designer is God, is remarkably still a matter of faith). So the primacy of faith is not compromised. I do not agree with the position that religious faith in Creator has scientific evidence in the strict sense of this word. It has pointers to it, for want of a better word, not scientific evidence. Otherwise, it is not faith anymore but a 'proved theorem'. However, design is a different matter, strictly speaking. Design is only compatible with religious faith in the Creator of everything and the Giver of moral law, but strictly speaking does not entail it.EugeneS_{September 5, 2015
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Alicia Cartelli: Nature is the ultimate trial-and-error experiment, it hasn’t needed foresight to produce the diversity of species (…) we see today.
Natural selection can only operate on viable organisms. IOW the production of viable organisms is entirely up to chance — trial-and-error. It’s relevant to quote Dawkins here:
But, however many ways there may be of being alive, it is certain that there are vastly more ways of dead, or rather not alive. You may throw cells together at random, over and over again for a billion years, and not once will you get a conglomeration that flies or swims or burrows or runs, or does anything, even badly, that could remotely be construed as working to keep itself alive. [Dawkins]
Natural selection has zero creativity; all it does is eliminate viable organisms — which isn’t helpful. So, how did humans come into existence? Evolutionist: “By chance alone, despite natural selection.”Box_{September 5, 2015
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Alicia Cartelli: When I use the word function, I am simply referring to what the molecule does, due to its chemistry; no evolutionary perspective or “implementation logic” involved.
It is utterly nonsensical to look at a molecule in isolation and term its involvement in chemical reactions “function”. It doesn't make sense, because one cannot speak coherently about “function” without the context of a larger system. “Function” is teleological and always implies a hierarchical relationship.Box_{September 5, 2015
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UB, Virgil Cain Apparently this is the closest the AAs physically get to the mRNA codons: (mRNA codons) - (tRNA anticodon + tRNA CCA tail) - AA My question is: how do the aminoacyl tRNA synthetase enzymes associate the tRNA anticodons with the corresponding AAs? Where is that correspondence established? When? I'll try to look for that info, but if someone else can post it here, I will appreciate it. Thanks. - clueless studentDionisio_{September 4, 2015
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UB and Virgil Cain This mRNA translation discussion seems a little off topic for this thread, but that's fine with me. Since the transcription and translation mechanisms seem consistent through most cell types, I did not study them until this discussion now. I've ben more interested in the processes that cause the cellular diversity and their spatiotemporal distributions into interwoven tissues and organs within the biological systems. There's where design really shines. But now that I finally looked into this fundamental genetic mechanism I think I understood your point about the physical discontinuity of the mechanistic components of the protein synthesis process. Perhaps the below text made me understand your point:
The amino acid loaded onto the tRNA by aminoacyl tRNA synthetases, to form aminoacyl-tRNA, is covalently bonded to the 3'-hydroxyl group on the CCA tail. (Wikipedia)
Apparently the enzyme does the association between the tRNA anticodon and the corresponding AA. Hence, the AAs don't seem to have direct physical association to the anticodons. The association seems to be mediated by the given enzyme. Apparently the AAs get consistently attached to the CCA tails of corresponding tRNA molecules. The anticodon domains of the tRNA are the physical connection to the corresponding mRNA codons. The mentioned enzyme is the heroe that realizes the association between the anticodon domains of the tRNA and the AAs. Hence, in no moment the AAs appear directly bound to the codons or anticodons. Did I get this right now? Thanks.Dionisio_{September 4, 2015
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You’ll have to figure out a way to convince me that you are you. Even better, convince him that you are not someone else. That's what I did. Hint: He accepts DNA samples.Mung_{September 4, 2015
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Dio, Send me an email to contact (-at-) complexitycafe (-dot-) com and I'll answer your question directly. You'll have to figure out a way to convince me that you are you. :)Upright BiPed_{September 4, 2015
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